Film and sprocket-drum.



` UNITED STATES; PATENT OFFICE.

OSCAR J. IIOLIILES, or CHICAGO, ILLINOIS, ASsIGNOR To ATLAS EDUCATIONALFILM Oo., or CIIIcAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

FILM AND sPnOCKET-DRUM.

T0 all .whom it may concern:

'Be it known that I, OSCAR J. HOLMES, 'a citizen of the United States ofAmerica, and a resident of Chicago, in the county of Cook, State ofIllinois, have invented certain new and useful Improvements in' Filmsand Sprocket-Drums, -of which the following is a specification.

This invention relates to that class of moving picture mechanisms inwhich a sprocket` drum -is'employed to positively feed the pictured filmthrough the mechanism. And the present improvement has for itsobjcct toprovide a simple and efficient structural formation of the sprocketperforations in the pictured film or web, and the coacting with whichthe surreptitious use ofl an ordinary iniammab-le. film having. standardSprocket. perforations is prevented, and

which on the other hand admits of a non-inflammable film of 'the presentformation in the ordinary moving picture mechanisms `having a' standardformationof their film In the accompanymg feeding sprocket drums, all aswill hereinafter more fullyappear. 4

drawings z-Figure l, isa detail sectional elevation of a sprocket drumand a fragmentof a moving picture film, villustrating the 'preferredform of the. present invention,'the film being shown in section. Fig.V2, is a rear elevation of the same. Fig. 3, is a view similar to Fig.1, showing a modification. Fig. 4, is a rear 4elevation of the same.

Similar reference numeralsindicate like parts in the several views.

' In. the usey of moving picture exhibitions for educational and likelpurposes in school rooms and the like, it is necessary that anon-injiammable and safe film be used and i the' surreptitious use of aninflammable and dangerous film be prevented. And an additionalrequirement from a commercial Standpoint is that vsuch.non-inflaml'nableand safe film is capable of use in connection with standard form of lmfeeding sprocket drum of an ordinary moving picture mechanism, and tothe above ends the present invention comprises a structural formationand association of parts as follows: A,

Referring to Figs. 1 and 2,' a sprocket `drum designated as 5 has formedon its pe-V, riphery a plurality of alternating sprockgf" teeth 6 and 7,With the series of sprocket/and'a'sprocket drum formedwith a-series ofliO Sp'ecication ofLetters Patent. Application mea Aprii 5, 1915.'serial No. 19,140.

Patented June 29, 1915,.

I teeth 6 of the standard size and spacing,

,While the serles of sprocket teeth 7 are of the standard spacing butare made o f ai larger Size or extent, preferably by beingincreased bothin height and in one direction ing` picture film or Web -formed with thecorresponding plurality of alternating sprocket perforations 9 and 10,with the sev i ries of perforations 9 of the standard size and spacing,While the series of perforations 10 have the standard spacing butaremade of a larger size or extent, and preferably by being increased inlength in one direction from the imaginary spacing lines of theplurality of perforations.

In the construction illustrated in Figs. 3 and 4, the entireplurality ofsprocket teeth 6 on the periphery of the sprocket drum 5 are of astandard size and spacing, with alternate pairs of said sprocket teethconnected together by intermediate Webs 7,v

which are adapted to perform the functions of the enlarged Sprocketteeth 7 heretofore described. And in connection with said formationshown in Figs. 3 and 4;, the companion moving picture film` 8 is formedwith a corresponding series of sprocket perforations 9 of a standardsize and spacing, and With alternate pair! of said peforations connectedtogether by intermediate slits -or passages'JlO corresponding with andreceiving-the Webs 7 aforesaid.

Having thusfully describedI my said invention, what Iy claim as new anddesire to secure by Letters Patent, is

1.v A moving picture film formed with a series of. sprocketperforationsihaving a standard spacing with alternate perforations ofthe series having a greater extent, substantially as set forth.

2; A moving picture film formed With..a series of sprocket perforationshaving a standard-spacing with alternate perfora- Vtions of the serieshaving a greater extent in one direction from their normal centralconstruction lmes, Substantially asset `forth.

3. InV a moving picture mechanism, the

combination of a moving pioturelm for'med with a series of sprocketperforations having a standard spacing With alternating perfo- ''ationsofthe/series having agi-eater extent,

BEST AVAILABLE COPY sprocketfteeth having a standard spacingA withalternate teeth oltheseries having greuter'extent, substn'tiallvas'set'forth.

al. in zt moving picture mechanism7 the combination of n moving picturefilm"` formed withv fr series' of sprocket perforatiens having astandard spacing with alterhating perforations of the series having agreater extent 1nl one direction from their normal construction lines,and :L sprocket vdrum formed 'vvith a series of sprocket teeth of April,1915. v

OSCAR J. HOLMES.

